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On the radiative corrections in the Horava–Lifshitz z=2 QED
No full textAbstractWe calculate one-loop contributions to the two and three point spinor–vector functions in z=2 Horava–Lifshitz QED. This allows us to obtain the anomalous magnetic moment
A phase III observer-blind randomized, controlled study to evaluate the immune response and the correlation with nasopharyngeal carriage after immunization of university students with a quadrivalent meningococcal ACWY glycoconjugate or serogroup B meningococcal vaccine
No full textAbstractBackgroundUniversity students have high rates of pharyngeal carriage of Neisseria meningitidis. Interruption of carriage acquisition is an important mechanism of vaccines for inducing herd protection. 4CMenB and MenACWY-CRM vaccines have been shown to be immunogenic against meningococcal serogroups B and ACWY respectively in younger age groups, and also to elicit a modest impact on meningococcal carriage in vaccinated students. However, vaccine responses in university students and the impact of serum bactericidal antibody (SBA) titers on meningococcal carriage are undetermined.MethodsImmunogenicity of two 4CMenB doses or one MenACWY-CRM dose was measured in university students at Months 2, 4, 6 and 12 post-first vaccination. Immunogenicity of one MenACWY-CRM dose in students with previous meningococcal serogroup C conjugate vaccination was also assessed. Immune responses were measured with an SBA assay using human complement (hSBA) against three reference strains for serogroup B and against one strain for each for serogroups C and Y. Correlations between hSBA titers and meningococcal carriage were analyzed.ResultsAll subjects demonstrated robust functional antibody responses to both vaccines at Month 2 and a high proportion maintained protective hSBA titers up to Month 12. At baseline, carriage of disease-associated serogroup B strains and serogroups C and Y were higher in subjects with already-protective hSBA titers. Post-vaccination, while both 4CMenB and MenACWY-CRM elicited robust immunogenicity in students, significant correlations between post-vaccination hSBA titers and carriage of disease-associated serogroups were not observed.Conclusions4CMenB and MenACWY-CRM were both highly immunogenic. There was no correlation between carriage and post-vaccination hSBA titers
Ammonium sulfate preparation from phosphogypsum waste
No full textAbstractThe Egyptian phosphogypsum waste is treated using sulfuric acid prior the ammonium sulfate production. The relevant factors that would affect the removal efficiencies of some impurities are studied. The optimum conditions of the treatment are 8 M sulfuric acid solution and 1/4 solid/liquid ratio for 30 min contact time at 80 °C. Moreover, the optimum conditions of the ammonium sulfate preparation are 10 g of the suspended impure or purified phosphogypsum in 40 ml of 3% ammonium sulfate solution (as initiator), 1/4 solid/liquid ratio at pH7 at an addition of an excess ammonium carbonate, and 150 rpm stirring speed for 4.0 h contact time at 55 °C as well as the 5 mg of barium chloride is added to remove the radium in the ammonium sulfate product. Finally, the ammonium sulfate is crystallized and the chemical analysis of the product shows 20% nitrogen and 23.6% sulfur. Therefore, the purity of the obtained ammonium sulfate is 95% from the purified phosphogypsum
Modelling of artefacts in estimations of particle size of needle-like particles from laser diffraction measurements
No full textAbstractManufacturing of particulate products across many industries relies on accurate measurements of particle size distributions in dispersions or powders. Laser diffraction (or small angle light scattering) is commonly used, usually off-line, for particle size measurements. The estimation of particle sizes by this method requires the solution of an inverse problem using a suitable scattering model that takes into account size, shape and optical properties of the particles. However, laser diffraction instruments are usually accompanied by software that employs a default scattering model for spherical particles, which is then used to solve the inverse problem even though a significant number of particulate products occur in strongly non-spherical shapes such as needles. In this work, we demonstrate that using the spherical model for the estimation of sizes of needle-like particles can lead to the appearance of artefacts in the form of multimodal populations of particles with size modes much smaller than those actually present in the sample. This effect can result in a significant under-estimation of the mean particle size and in false modes in estimated particles size distributions
Detection of minor and trace elements in powdered milk
No full textAbstractPassive gamma ray spectrometry and neutron capture prompt gamma activation analysis (PGAA) were used to investigate powdered cow's milk samples [termed optimal (1), optimal (2) and optimal (3)] collected from local markets in the city of Cairo, Egypt. Standard material with a total average activity of 0.830±0.2μCi and a certified reference material [IAEA (A-14)] were used to study the accuracy of a passive multi-gamma ray measurement method. Three powdered milk samples of the same geometry and volume were used in this analysis. The specific activity of 226Ra ranged from 24.5±2.1 to 114±1.2Bq/kg, 232Th from 8±1 to 14±1.2Bq/kg and 40K from 444±28 to 1826.1±3.1Bq/kg, all of which were higher than the activities corresponding to the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR) (50, 50 and 500Bq/kg for 226Ra, 232Th and 40K, respectively). The average dose rate at 1cm for 40K ranged from 8.21E−02±0.12 to 3.3E−1±0.22mSv/h/cm. We also showed that 208Tl81, 212Pb82 and 212Bi83 should be considered products of thorium. k0-PGAA was carried out using an integrated and calibrated prompt gamma ray system with a neutron flux of 106n/cm2 per second. The thermal to epithermal neutron flux ratio (f) and cadmium ratio were measured using a thin gold foil technique (ration=160). Different Cl concentrations were prepared as standards for k0-PGAA. The elemental concentrations of Na, Mg, Al, Ca, Mn, Fe, Cu, Ga, Zn, As, Se, Cs, Cd, In, Th and I were measured in the three powdered milk samples. The mean±standard deviation ranges of the elements were as follows: Na=1069±49–1583±53ppm, Mg=347±13.64–385±16.71ppm, Al=45±1.30–72±2.40ppm, Fe=5500±110–7123±130ppm, Zn=107±3–123±6ppm, Ca=4200±72–5483±81ppm, Mn=1269±69–1784±72ppm, Pr=1.7±0.02–2.6±0.07ppm, Ga=265±5–293±8ppm, Cu=57±0.5–64±0.9ppm, In=1000± 38.64–1574±41.34ppm, Cd=6.1±2.71–12.6±4.11ppm, I=53±0.09–62±1.18ppm, Cs=4±1.56–11±4.22ppm, As=26±0.66–29±0.89ppm, Se=126±4.8–144±5.7ppm, Th=47±1.0–78±6.0ppm
The role of quantitative systems pharmacology modeling in the prediction and explanation of idiosyncratic drug-induced liver injury
No full textAbstractIdiosyncratic drug-induced liver injury (iDILI) is a serious concern in drug development. The rarity and multifactorial nature of iDILI makes it difficult to predict and explain. Recently, human leukocyte antigen (HLA) allele associations have provided strong support for a role of an adaptive immune response in the pathogenesis of many iDILI cases; however, it is likely that an adaptive immune attack requires several preceding events. Quantitative systems pharmacology (QSP), an in silico modeling technique that leverages known physiology and the results of in vitro experiments in order to make predictions about how drugs affect biological processes, is proposed as a potentially useful tool for predicting and explaining critical events that likely precede immune-mediated iDILI, as well as the immune attack itself. DILIsym, a QSP platform for drug-induced liver injury, has demonstrated success in predicting the presence of delayed hepatocellular stress events that likely precede the iDILI cascade, and has successfully predicted hepatocellular stress likely underlying iDILI attributed to troglitazone and tolvaptan. The incorporation of a model of the adaptive immune system into DILIsym would represent and important advance. In summary, QSP methods can play a key role in the future prediction and understanding of both immune-mediated and non-immune-mediated iDILI
A radiative model of quark masses with binary tetrahedral symmetry
No full textAbstractA radiative model of quark and lepton masses utilizing the binary tetrahedral (T′) flavor symmetry, or horizontal symmetry, is proposed which produces the first two generation of quark masses through their interactions with vector-like quarks that carry charges under an additional U(1). By softly-breaking the T′ to a residual Z4 through the vector-like quark masses, a CKM mixing angle close to the Cabibbo angle is produced. In order to generate the cobimaximal neutrino oscillation pattern (θ13≠0,θ23=π/4,δCP=±π/2) and protect the horizontal symmetry from arbitrary corrections in the lepton sector, there are automatically two stabilizing symmetries in the dark sector. Several benchmark cases where the correct relic density is achieved in a multi-component DM scenario, as well as the potential collider signatures of the vector-like quarks are discussed
Pre- and unplanned walking turns in Parkinson’s disease – Effects of dopaminergic medication
No full textAbstractAlthough dopaminergic medication improves functional mobility in individuals with Parkinson’s disease (PD), its effects on walking turns are uncertain. Our goals was to determine whether dopaminergic medication improves preplanned and unplanned walking turns in individuals with PD, compared to healthy controls. Nineteen older adults with mild-to-moderate PD and 17 healthy controls performed one of the following three tasks, presented randomly: walking straight, or walking and turning 180° to the right or left. The walking direction was visually cued before starting to walk (preplanned) or after (unplanned, i.e., 0.6m before reaching the turning point). Subjects with PD were assessed off dopaminergic medication (OFF) and on dopaminergic medication (ON) medication. Turning strategy (step and spin turns), turning performance (turning distance and body rotation) and walking pattern were analyzed for three turning steps. Irrespective of medication state and turning condition, step and spin turns followed a nearly 50:50 distribution. After intake of dopaminergic medication, subjects with PD increased their turning distance but not the amount of body rotation or their walking pattern. Compared to controls, turning impairments in subjects with PD remained while ON medication and problems regulating step width were the most prominent features of their walking pattern. Specifically, subjects with PD turned with narrower cross-over steps, i.e. when the external foot crossed over the line of progression of the internal leg. We conclude that turning impairments remained even after dopaminergic medication and problems modulating step width appears to be a critical feature for turning in PD
Diagnostic accuracy of the combined use of conventional sonography and sonoelastography in differentiating benign and malignant solitary thyroid nodules
No full textAbstractObjectiveTo assess the diagnostic accuracy of combined use of conventional grayscale US and sono-elastography in differentiating benign and malignant solitary thyroid nodules.Materials and methodsThis prospective study included 50 patients with solitary thyroid nodules being evaluated using grayscale US followed with sono-elastography (USE). Suspicious conventional sonographic data for malignancy then evaluated using USE were classified according to Rago criteria with calculation of strain ratio. The diagnostic performances of grayscale US, elastography with Rago criteria, for predicting thyroid malignancy were compared and cutoff value for strain ration was statistically analyzed. Finally all patients with solitary nodule were subjected to US-guided FNAC and 35 patients recommended for surgery in the form of 12 patients underwent total thyroidectomy and 23 patients underwent thyroidectomy with neck dissection.Results30 females (60%), and 20 males (40%) were included (Mean age 38) with final diagnosis comprised 29 (58%) pathologically proved benign thyroid nodules and 21 (42%) pathologically proved malignant nodules. US showed significant relation between markedly hypo-echogenicity, oval than tall, margin irregularity, presence of micro-calcification with diagnosis of thyroid malignancies with p value <0.001. Regarding sonoelastography, there was significant relation between elastography scores 4 and 5 and thyroid malignancies showing sensitivity of 80%, a specificity of 100%, and p value <0.001. The most accurate strain ratio cutoff value among studied cases was 2.52. Combination of grayscale US and sono-elastography yielded better results with sensitivity of 92%, specificity of 95%, PPV of 89%, NPV of 92% and diagnostic accuracy or efficacy of 96%.ConclusionCombined use of USE and grayscale US, showed superior performance in the differentiation of malignant and benign thyroid nodules compared with each technique alone. Suspicious US criteria with elasticity Rago scores 4 and 5 and strain ratio more than 2.52 are the most predictive signs of malignancy
Data on metal levels in the inlet and outlet wastewater treatment plant of hospitals in Bushehr province, Iran
No full textAbstractIn this paper, we measured the levels of metals including Pb, Cr, Cd, Ni, Hg, Fe, and Cu in the inlet and outlet wastewater of hospitals. The samples were taken from wastewater in Bushehr׳s province hospitals, Iran. After the collection of samples, the concentration levels of metals were determined by using graphite furnace absorption spectrometer (AAS) method (Varian, SpectrAA 240, Australia). Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16)